Title : Catalytic biotransformations by Peroxidases

Abstract:

Heme enzymes known as peroxidases (E.C.1.11.1.7) use hydrogen peroxide as an electron acceptor to catalyse a variety of oxidative processes. There are two significant environmental challenges that are driving the current interest in catalytic bioconversions. (i) Using H₂O₂ as an environmentally benign oxidant to replace or substitute heavy metal salts and other reagents used in conventional oxidations. (ii) The main problem is the growing interest in producing chemicals in chemical processes with high chemoselectivity, regioselectivity, and stereoselectivity in order to produce superior byproducts. Peroxidases, a type of redox enzyme, are crucial in achieving these two objectives. The fruit juice-derived enzyme had a high peroxidase activity of around 9.0 IU. To explore the catalytic potential of the peroxidase enzyme, the rate of reaction catalysed by the enzyme was determined using guaiacol as the substrate and in the presence of various oxidising agents. It was discovered that V₂O₅ was a better oxidising agent than H₂O₂ in this experiment. By releasing Br₂ and I₂, the enzyme encourages the halogenation process. When Ca²⁺, Mg²⁺, and Cd²⁺ are present, enzyme activity is increased; when Zn²⁺ and Ni²⁺ are present, enzyme activity is decreased. These metal ions' nature of inhibition has also been studied.

Keywords: Redox enzyme; Peroxidases; Biotransformations; Halogenation; Bioremediation.

Biography:

Dr. Meera Yadav completed her Master’s and Ph.D in Chemistry from DDU Gorakhpur University, Gorakhpur, Uttar Pradesh,  India. She was awarded CSIR-SRF (2000-2003), twice as DST- Woman scientist A (2005-2008) & (2013-2016) and UGC- Dr. D. S Kothari Postdoctoral Fellow (2009-2012) at Department of Chemistry, Gorakhpur University, Gorakhpur. Her research area includes, purification, characterization and applications of Metalloenzymes- Lignin peroxidase, Mn-peroxidase, Laccase and Chloroperoxidase, isolation of fungal strains producing ligninolytic enzymes, their structural-functional studies using X-ray crystallography, spectroscopic and fast reaction kinetic techniques. Use of enzymes in synthetic inorganic and organic chemistry. She has served two years as guest lecturer in Madan Mohan Malviya Technical University (MMMTU), Gorakhpur. Currently she is working as an Assistant professor in the Department of Chemistry, North Eastern Regional Institute of Science and Technology (NERIST), Nirjuli, Itanagar, Arunachal Pradesh, India. She has attended and participated in more than 30 national and international seminars and conferences. She has guided one Ph.D and five students are being involved in various research activities in her laboratory. Eight students have submitted their M.Sc dissertation under her guidance till now. She has published more than 40 research papers in reputed national and international peer reviewed journals and reputed standard books. She has also reviewed many research papers. She is life member of American Chemical Society, Indian Council of Chemists and Indian Society of Chemists and Biologists.